What could be the result from over vibration while pouring the concrete?

• A. Uniform compaction
• B. Segregation
• C. Faster strength gain
• D. Increased durability

Answer: (B)

Vibration helps concrete settle and remove air pockets, but only to the point where the mix stays together. If you over-vibrate, the heavier aggregates tend to settle toward the bottom while the cement paste and finer particles are squeezed upward. This separation of components is segregation. You’ll often see a dense layer of aggregate at the bottom with a paste-rich, lighter layer near the top, plus surface laitance and potential voids or honeycombing. That weakens the bond and can reduce strength and durability. So the result of over-vibration is segregation, not uniform compaction, not faster strength gain, and not increased durability.